Correlation between the amount of <i>C. burnetii</i>-specific IFN-γ production and the number of IFN-γ positive cells.

<p>The individual values of chronic Q fever patients (n = 16) were used to determine the correlation between the IFN-γ production as measured with the IFN-γ production assay, and the number of IFN-γ positive cells as measured with the <i>Coxiella</i> ELISPOT. Each graph shows the correlation between the resulting values of the two assays, with either one of the stimulating antigens. On the Y-axes, the IFN-γ production is shown after stimulation with NMI (upper graphs) and Henzerling antigens (lower graphs). On the X-axes, the spot count is shown after stimulation with NMI (left graphs) and NMII (right graphs) antigens. The Spearman’s correlation coefficient <i>r</i> (95% Confidence Interval) is given for each comparison. Abbreviations: NMI, Nine Mile phase 1; NMII, Nine Mile phase 2; IFN-γ, interferon-gamma.